Super Stock leaf springs

I will find out this week . the back half of the car is currently sitting on 3 concrete blocks on each side and rear end is hanging from from shackles / KYB shocks. I have 2 slotted mag rims with tires I will mount them on the car . the other issue was brought up is if the car is driving down the road and hits a large bump and the body bounces and the shackles return to the wrong position ?
When you pop em down to the way they belong, are the shackles angled toward the bumper or to the rearend?
If they are angled toward the bumper, with car weight on them they should stay that way. (That's how they are supposed to be)